U.S. Pat. No. 4,990,181 is directed to porous sintered aluminide structures of aluminum, nickel, titanium and/or rare earth metal.
U.S. Pat. No. 4,850,717 teaches a process sensor tube having erosion and corrosion resistance which is adapted for sensing process conditions which has a coating of an aluminide of nickel.
U.S. Pat. No. 4,867,116 teaches a spark-ignited internal combustion engine exhaust valve having on the critical surfaces thereof nickel aluminide.
U.S. Pat. No. 4,769,210 teaches an apparatus for use in liquid alkali environment such as nuclear fuel sub-assembly which has bearing surfaces coated with nickel aluminide.
U.S. Pat. No. 4,762,558 pertains to the production of reactive sintered nickel aluminide material utilizing hot isostatic compaction.
U.S. Pat. No. 4,676,829 pertains to cold worked tri-nickel aluminide.
U.S. Pat. Nos. 4,650,519 and 4,661,156 pertain to hot isostatic pressing of nickel aluminide from powder. In a similar fashion, see U.S. Pat. Nos. 4,613,480 and 4,609,528.
U.S. Pat. No. 4,495,252 teaches a wear-resistant metallic article employing a mixture of nickel aluminide in a copper-based matrix.
U.S. Pat. No. 4,362,696 teaches corrosion-resistant fuel cladding alloy for liquid metal fast-breeder reactors which utilizes nickel aluminum inter-metallic phases.
Other patents related to aluminide alloys are U.S. Pat. Nos. 3,970,450; 4,144,059; 4,238;229; 4,253,872; 4,410,371; 4,612,165; 4,647,427; 4,711,761; 4,722,828; 4,731,221; 4,839,140; 4,961,903; and Canadian Patent No. 1,244,676.
Improvement To The Art
The general deficiencies of metallic elements and their alloys when used as tooling, fixturing, components and general structural items (parts) for use at elevated temperatures (i.e. 1200.degree. F, to 2300.degree. F.) is as follows:
the strength and toughness values diminish as the temperature increases rendering parts made from such materials less useful in withstanding structural loads, especially beyond 1500.degree. F. to 2300.degree. F.; PA0 the resistance to attack by oxygen diminishes with increasing temperatures rendering parts made from such materials vulnerable to dimensional loss, load bearing failure, loss of surface integrity, and general incapacity to perform their function, especially with temperatures beyond 1200.degree. F. to 2300.degree. F.; PA0 the resistance to creep and fatigue diminishes with increasing temperatures along with the strength and toughness rendering parts made from such materials vulnerable to thermal shock, thermal cycle fatigue, load cycle fatigue, cracking, dimensional loss, load bearing failure, breakage, and general incapacity to perform their function, especially beyond 1500.degree. F. to 2300.degree. F.; PA0 the resistance to attack by carbon diminishes in many of these materials with increasing temperatures rendering parts made from such materials vulnerable to embrittlement, load bearing failure, and general incapacity to perform their function, especially beyond 1500.degree. F. to 2300.degree. F.; and PA0 the resistance to abrasive wear diminishes in parallel to the general decline in strength and toughness rendering parts made from such materials vulnerable to galling, welding, seizing, loss of dimensional integrity, and general incapacity, especially beyond 1200.degree. F. to 2300.degree. F.
However, there is a class of metal alloys that provides the basis for significant improvement in the aforementioned performance deficiencies which arise at elevated temperatures and in turn permits one to make industrially useful parts that provide a significantly better performance than parts made from their generally available metallic alloy counterparts. This class of metal alloys are the intermetallic alloys or inter-metallic compounds which are defined as an alloy or compound of two or more metals which has a distinctive crystallographic structure and definite composition or composition range.
It is an object of the present invention to provide material handling apparatus for processing heated formed ferrous metal products and/or hot glass products fabricated of intermetallic alloys of a face centered cubic crystal of a metal aluminide.
It is another object of the present invention to provide fixtures and components (i.e. parts) that are useful for the processing, fabrication and manufacture of hot steel objects based on the application of inter-metallic alloys as parts, especially the alloys based on the face centered cubic crystal of a metal aluminide.
It is also an object of the invention to provide a heat treatment furnace roll of an inter-metallic alloy as used in the support and transfer of hot steel objects within steel heat treat furnaces with the said rolls having the property of withstanding the load bearing requirements, the resistance to oxidation, the resistance to scaling, the resistance to wear, the resistance to carburization, the resistance to creep and fatigue and generally the ability to usefully be applied in the operating environment.
It is also an object of the invention to provide a heat treat furnace roll made of an inter-metallic alloy that has the ability to retain its ultimate tensile strength at 1600.degree. F. of at least 75% of the ultimate tensile strength that the heat treat furnace roll had at ambient temperature, and further provide useful structural load bearing capacity at temperatures up to 2300.degree. F.
It is a further object of the invention to provide a steel slab soaking furnace roll made of an intermetallic alloy as used in the support and transfer of steel slabs in soaking furnaces that has the ability to be useful at temperatures up to 2300.degree. F. without regard to roll cooling wherein such a roll is able to provide useful load bearing capability, resistance to wear, resistance to oxidation and scaling and general useful product life in this application.
It is also an object of the invention to provide tubes and other industrial fixturing and components (i.e. parts) made of an intermetallic alloy as used in furnaces and in other unit operations for steel that have the ability to withstand the effects of carbon on such parts which often lead to embrittlement, cracking and failure of such when used at elevated temperatures (e.g. 1400.degree. F. to 2300.degree. F.) whereby such parts would be subjected to carburization, whether intentionally when such parts are used in the unit operation of carburization of steel objects or whether such are merely exposed to such conditions as a matter of course.
It is a further object of the invention to provide tools made of intermetallic alloys which are to be used in the manufacture of steel products from steel raw materials (e.g. rolling, forming, piercing, extrusion, drawing, swaging and other such unit operations) at elevated temperatures, especially within the temperature range of 1400.degree. F. to 2300.degree. F. wherein such tooling should retain at least 75% of its ultimate tensile strength at 1600.degree. F. in comparison to the strength of the tool at ambient temperatures.